Bucky slot radiation shield for an X-ray table

ABSTRACT

Three shield panels or doors, respectively, for the head-end, center and foot-end portion of an X-ray table which together with the front portion of the bucky assembly are adapted to cover all of the bucky slot in the front of the table by selectively pivoting from a horizontal or open nonshielding position to a vertical or closed shielding position when the bucky is parked during a period of non-use at either the head-end or foot-end of the table. The door associated with the end of the table where the bucky is parked for example during the fluoroscopic mode, remains in the horizontal position; however, the movement of the bucky to the &#39;&#39;&#39;&#39;park&#39;&#39;&#39;&#39; position causes the end door at the other end to raise to the vertical position while raising the center door along with it. When the bucky is in the normal use position, all three shield panels or doors are swung out of the way in the horizontal, i.e. non-shielding position.

United States Patent 1 Sweeney et al.

[ Sept. 2, 1975 BUCKY SLOT RADIATION SHIELD FOR AN X-RAY TABLE [75] Inventors: Thomas Michael Sweeney; Robert L.

Guentner, both of Baltimore, Md.

[73] Assignee: CGR Medical Corporation,

Baltimore, Md.

[22 Filed: Aug. 1, 1974 [21] Appl. N0.: 493,894

[52] US. Cl 250/515; 250/508 [51] Int. Cl. G21F 3/00 [58] Field of Search 250/444-450,

[56] References Cited UNITED STATES PATENTS 3,030,508 4/1962 Mort et al l. 250/448 Primary ExaminerDavis L. Willis Attorney, Agent, or FirmBrady, OBoyle & Gates [5 7] ABSTRACT Three shield panels or doors, respectively, for the head-end, center and foot-end portion of an X-ray table which together with the front portion of the bucky assembly are adapted to cover all of the bucky slot in the front of the table by selectively pivoting from a horizontal or open nonshielding position to a vertical or closed shielding position when the bucky is parked during a period of non-use at either the headend or foot-end of the table. The door associated with the end of the table where the bucky is parked for example during the fluoroscopic mode, remains in the horizontal position; however, the movement of the bucky to the park" position causes the end door at the other end to raise to the vertical position while raising the center door along with it. When the bucky is in the normal use position, all three shield panels or doors are swung out of the way in the horizontal, i.e. non-shielding position.

12 Claims, 8 Drawing Figures BBQ- 3,425

SHEET Qzw -58 BUCKY SLOT RADIATION SHIELD FOR AN X-RAY TABLE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to X-ray apparatus, and more particularly to means for protecting operating personnel from secondary radiation emanating from the bucky slot at the front of an X-ray table.

2. Description of the Prior Art X-ray tables adapted for both radiographic and fluoroscopic modes of operation include a movable cassette holder or bucky in the table which is adapted to move from one length of the table to the other. In order to accommodate the bucky, the table includes an endto-end opening or bucky slot which requires a radiation shield in order to protect operating personnel from secondary radiation which would normally escape through the slot during fluoroscopic examinations since at that time the bucky is not used and parked at one end of the table and since the Xray tube used therefor is located beneath the table, In the radiographic mode of operation, however, the bucky does come into use and is moved about the center of the table. Proper shielding in such operation, however, is provided by a second overhead X-ray tube and collimator mounted on the spot film tower associated with the table.

Previous attempts to provide the required shielding has suffered from the disadvantage that less than 100 percent shielding is provided while using overly complex mechanisms which sometimes occupied space normally needed for other table mechanisms. Additionally and probably most importantly of all, prior art arrangements placed a drag on the bucky during normal use at the center of the table. Such arrangements, for example, may include folding panels or window-shade type bands attached to the bucky. Still other arrangements may include a plurality of upwardly biased strips which are adapted to be knocked down by means of a deflector attached to the bucky as the bucky is moved along the table length.

Patented art of which the applicant is aware constitutes the following US Pat. Nos. 1,907,523, Egressi, et

al.; 2,718,598, Graf; 2,835,824, Schepker; and 3,030,508, Mort, et al.

SUMMARY Briefly, the subject invention is comprised of three radiation shield panels or doors adapted to cover the bucky slot respectively at the foot-end, center and head-end of an X-ray table when an X-ray cassette holder or bucky is in a park position at either end of the table while moving out of the way to uncover bucky slot whenever the bucky moves away from the park position towards the center of the table. The three panels are pivoted along a common longitudinal edge adjacent the bucky slot and are adapted to be normally biased down in a horizontal position by spring bias means attached to the center door. The far end portions of the doors respectively located at the foot-end and headend of the table include a lever arm which is coupled to pulley means which are adapted to be operated by the bucky only when the park position is reached at either end of the table and thus drag-free operation of the bucky is provided. While the bucky is away from the park position, the pulley means are inoperative and have no effect on the three doors which are held down in the open or horizontal position by the center door. The bucky, however, includes means which are adapted to engage the pulley means at the park position which operates the door at the opposite end of the table causing it to raise to the vertical position to partially cover the slot. The end doors additionally include a respective tab at the center end which is adapted to contact the rear surface of the center door and raise it whenever either end door is raised as the bucky moves to the park position at the opposite end of the table.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an X-ray table having a bucky slot with a bucky therein parked at the headend of the table;

FIG. 2 is a vertical plan view of the preferred embodiment of the subject invention interiorally located beneath the table top of the X-ray table shown in FIG. 1;

FIG. 3 is a front plan view partially in section of the apparatus shown in FIG. 2;

FIG. 4 is a fragmentary end plan view of the apparatus shown in FIG. 2 while the foot-end door is in the raised or shielding position;

FIG. 5 is a fragmentary end view illustrative of the foot-end door shown in FIG. 4 in the lowered or nonshielding position;

FIG. 6 is a first view illustrative of the mechanism included in the pulley means shown in FIG. 2 during the deactivated position;

FIG. 7 is a view illustrative of the mechanism shown in FIG. 6 being activated by the movement of the bucky to the park position at the foot-end of the table; and

FIG. 8 is a diagram illustrative of a second embodiment of pulleymeans adapted to operate the three shield panels or doors.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and more particularly to FIG. 1, reference numeral 10 denotes a conventional X ray table adapted for both fluoroscopic and radiographic use. The table 10 includes an end-to-end opening or bucky slot 12 in the front portion thereof beneath the table top 14. An X-ray tube, not shown, is located within the table 10 under the top 14 for fluoroscopic examinations. Another X-ray tube, not shown, adapted for radiographic use is mounted above the table on a tower assembly 16. During the radiographic mode an X-ray cassette is loaded into a cassette holder or bucky 18, shown in the park position at the headend of the table, and is selectively moved to a desired location intermediate the park positions at the head-end and foot-end of the table. During the radiographic mode, the X-ray beam is directed downwardly to the field of interest and onto the cassette contained in the bucky. Suitable radiation shielding is included in the means for directing the beam which may include, for example, a collimator. When, however, a fluoroscopic examination is desired, the bucky 18 is parked at either end of the table and the X-ray tube located beneath the table is utilized in combination with image amplifiers, TV monitors, etc, mounted above the table on the tower 16. In such a usage mode, if the bucky slot 12 is not closed in some manner to provide proper X-ray shielding, secondary radiation emanating from the tube located beneath the table is transmitted from the bucky slot to the radiologist and/or technician operating the equipment.

Accordingly, the subject invention is directed to shielding means for the bucky slot 12 during fluoroscopic examinations when the bucky 18 is not in use and is parked either at the head-end or foot-end of the X-ray table 10. Directing attention now to FIGS. 2 and 3, the means contemplated in a preferred form of the invention includes three shield panels or doors 20, 22 and 24 respectively for the head-end, center and footend portions of the bucky slot 12. The three doors 20, 22 and 24 and hinged along a common edge lengthwise so that they are adapted to pivot or swing from a horizontal or open non-shielding position to a vertical or closed shielding position for closure of the slot 12. The center door 22 has a pair of tension springs 26 and 28 attached near the upper edge thereof while their opposite ends are attached to a table frame member 30 so as to provide a bias or pulling action of the door 22 down to the horizontal position. The end doors 20 and 24 include projecting tabs 32 and 34 which are adapted to contact the rear side of the center door 22. If the bucky 18 is moved away from the park position either at the head-end as shown in FIGS. 1, 2 and 3, or the foot-end, the center door 22 will be pulled down by means of the bias springs 26 and 28. In doing so, the end tabs 32 and 34 attached to the end doors 20 and 24 will be engaged pulling the end doors into the horizontal position along with the center door. Thus when the bucky is being used in the radiographic mode, all three doors, 20, 22 and 24 will be pulled down in the horizontal position out of the way of the bucky travel by means of the spring biased center door 22.

In the fluoroscopic mode, the bucky 18 is not utilized and is moved to a park position at either end of the table. When the bucky 18 is in the park position, for example, at the head-end of the table as shown in FIGS. 1, 2 and 3, it is desirous that the bucky slot 12 be completely closed in order to prevent secondary radiation from escaping therefrom. Accordingly, the head-end door 20 and the foot-end door 24 have their outer end portions coupled to a cable 36 which is wound around pulley means comprising a pair of pulley assemblies 38 and 40 which are mounted in opposite rear corners inside of the table housing 42. The bucky 18 includes driver means including element 44 which is adapted to engage the pulley assembly 40 when the bucky 18 is parked at the head-end of the table as well as an identical driver element 46 located on the other side of the bucky which is adapted to engage the pulley mechanism 38 when the bucky is parked at the foot-end of the table. Intermediate the two park positions, the pulley assemblies 38 and 40 are not engaged and therefore the bucky 18 is movable drag-free thereof.

Before discussing the operational details of the pulley assemblies 38 and 40, attention is first directed to FIGS. 4 and which disclose the means for operating the end doors and 24. FIGS. 4 and 5 comprise fragmentary end views of the foot-end of the table including the foot-end door 24 and the pulley assembly 38. Since the means for both is the same, consideration of the means for rotating the foot-end door 24 will suffice for both. The door 24 itself is bonded to one hinge 48 of the hinge assembly 50 mounted on the frame member attached to a plate 52 forming the front wall subassembly 54. A sheet metal lever arm member 56 includes an angulated end portion 58 is bonded to the front lower surface portion of the door 24 while the other end includes angulated portion 60 having an opening, not shown, which is adapted to be connected to the cable 36. The main body portion 62 of the lever arm member 56 thus lies in a vertical plane parallel to the end wall 63 of the table. A pulling force exerted by the cable 36 causes pivotal rotation of the lever member 56 about the hinge assembly 50. As will be shown subsequently, when the bucky 18 is moved away from the park position at either end of the table, cable 36 is lax and exerts no pulling force on either lever arm member associated with end doors 20 and 24 and thus both doors are pulled down by the spring biased center door 22. Returning to FIGS. 4 and 5, since the lever arm member 56 is secured to the door 24, it rotates counter-clockwise as shown in FIG. 5. On the other hand, when a pulling force is exerted on the cable 36 at the foot-end of the table, the lever member 56 will be rotated clockwise about the hinge assembly 50, causing the door 24 to close to a vertical positon as shown in FIG. 4.

Referring now to FIGS. 4, 6 and 7, there is disclosed the details of the pulley means comprising assemblies 38 and 40. Since both assemblies are identical, only one assembly 38 will be considered, The assembly 38 is comprised of two pivoted links 64 and 66 and two pulley wheels 68 and 70 which are in engagement with the cable 36. The smaller link 64 is pivotally secured by means of a pivot post 71 to an angulated end portion 72 of a bracket member 74 (FIG. 4). The smaller link 64 is pivotally connected to the longer link 66 at an intermediate point along its length by a pivot post 76. The pulley wheel 68 is rotatably mounted on pivot post 77 at one end of the link 66 while the other end includes a slot 78 which is adapted to slide on a pivot post 80 secured to an angulated end portion 82 of the angle bracket 74. Pulley wheel 70 is also mounted on pivot post 80.

FIG. 6 is illustrative of the condition of the pulley assembly 38 when out of engagement with the driver member 46 on bucky 18 shown in FIG. 2. FIG. 7 on the other hand illustrates what takes place when the bucky 18 is moved to the park position at the foot-end of the table. The driver member 46 includes a roller 84 or some such device which is adapted to engage the adjacent lengthwise edge 88 of the link 66. The movement of the bucky 18 to the park position causes the pivoted links 64 and 66 to retract toward the end wall 63 of the housing 42, causing the cable 36 to exert a pulling force on the door at the other end of the table, i.e. the door 20 at the head-end of the table, causing it to close. Closure of the head-end door 20 causes the center door 22 to close also due to the actions of the metal tab 32 which forces the door 22 upwardly along with the headend door 20.

Thus in operation, when the bucky 18 is parked at the head-end of the table 10 as shown in FIG. 2, the driver element 44 causes the pulley assembly 40 to retract and exert a pulling force on the lever arm 56 (FIG. 4) attached to the foot-end door 24 by means of the cable 36, causing it to close and due to the presence of the tab 34, causes the center door 22 to close also. As the bucky 18 is moved away from the park position at the head-end of. the table, the driver 44 disengages the pulley assembly 40 and is free to move to the other end of the table without any drag whatsoever from the doors 20, 22 and 24 and their associated operating assemblies. As the bucky 18 moves away from the park position at the head-end of the table 10, the springs 26 and 28 associated with the center door 22 urge the door to swing open into a horizontal position along with the head-end and foot-end doors and 24 due to the presence of the tabs 32 and.34. As the, bucky 18 is moved to the foot-end of the table and to the park position thereat, the driver element 46 engages the pulley assembly 38 causing a pulling force to be exerted by the cable 36 on the head-end door 20, causing it to close to a vertical position along with the center door 22.

It should also be pointed out that the length of the head-end and foot-end doors 20 and 24 are longer than the width of the bucky 18. As shown in FIG. 2 when the bucky for example is parked at the head-end of the table, the door 20 is open or in a down position. Accordingly, the space on either side of the bucky 18 to the center door 22 and the portion of the bucky slot at the far end of the table would provide a slot opening which is unshielded. To remedy this, the bucky assembly additionally includes bucky shield members 90 and 92 fabriacted on the front portion thereof to close the space ordinarily shielded by means of the door itself. Thus the center door 22 and either end door 20 and 24 along with the front portion of the bucky 18 itself and its associated shields 90 and 92 provide a shielded closure of the entire bucky slot 12 when the bucky 18 is parked at either the head-end or foot-end of the table during fluoroscopic modes of operation.

Referring now to FIG. 8, there is disclosed a second embodiment of the pulley means adapted to operate the head-end and foot-end doors 20 and 24. The assemblies 91 and 93 comprise identical pulley clusters located at the rear corner portions of the table 10, each having, for example, four stationary pulley wheels 94, 96, 98 and 100 around which the cable 36 is wound in such a manner that it goes around the pulleys 96 and 98 so that it is adapted to be contacted by the driver elements 44 and 46 of the bucky 18. Thus when the bucky reaches the park position at either end of the table 10, the cable 36 is forced between the two inner pulley wheels 96 and 98 towards the end wall 63 in order to exert a pulling force on the door at the opposite end of the table in the same manner as described heretofore. In such a configuration, the driver elements 44 and 46 actually comprise respective pulley wheels adapted to engage the cable 36. As shown in FIG. 8, the bucky 18 is parked at the head-end of the table whereupon the pulley wheel included in the driver 44 moves between the pulley wheels 96 and 98 of the cluster 93.

Thus what has been shown and described is three shield panels which are adapted to selectively cover the bucky slot by being pivoted on a hinged side from a horizontal non-shielding position to a vertical shielding position when the bucky is moved from one end of the X-ray table to the other and parked thereat.

Having thus described what is at present considered to be the preferred embodiments of the subject invention,

What is claimed is:

1. Bucky slot radiation shield apparatus in an X-ray table for protecting personnel from secondary radiation emanating from a radiation source under said table during an operational mode of said table, comprising in combination:

a movable X-ray film cassette holder referred to as a bucky;

an X-ray table having a bucky slot comprising a lengthwise opening in the front portion of said table to receive and permit selective movement of said bucky;

at least three hinged radiation shields mounted endto-end adjacent said bucky slot to individually pivot along a same respective edge from a first or open position to permit unobstructed passage of said bucky thereby to a second or shield position for closing the respective slot portion thereat, said three shields comprising a head-end shield, a center shield, and a foot-end shield;

bias means to bias said center shield normally to said open position;

first means forming part of each of said head-end and foot-end shields to extend over the rear portion of said center shield whereby both the head-end and foot-end shields will be moved to said normally open position along with said center shield and whereby pivoting to said shield position of either the head-end shield or foot-end shield will move said center shield to said shield position also;

second means forming part of each of said head-end and foot-end shields for individually actuating said shields when operated from said open position to said shield position; and

operator means coupled to said second means of said foot-end and head-end shields, becoming operable in response to said bucky traveling to and arriving at a predetermined location such as at the park position at one end of said table to operate said second means at the other end of said table.

2. The apparatus as defined by claim 1 wherein said three radiation shields comprise generally rectangular door elements having a length dimension substantially greater than the width dimension and additionally including hinge means coupling the same respective lengthwise dimension of said door elements to said table adjacent said bucky slot.

3. The apparatus as defined by claim 1 wherein said bias means comprises spring bias means.

4. The apparatus as defined by claim 3 wherein said spring bias means comprises a first second tension spring means respectively having one end coupled to the upper portion of said center shield along the lengthwise dimension opposite from said hinge means and having the respective opposite ends connected to said table.

5. The apparatus as defined by claim 1 wherein said first means comprises a respective overlapping tab element.

6. The apparatus as defined by claim 1 wherein said second means comprises a lever arm located on the outer end of each of said head-end and foot-end shields.

7. The apparatus as defined by claim 6 wherein said operator means comprises:

a first and second like pulley means located on said table opposite each other behind said foot-end and head-end radiation shields;

a common cable having one end attached to the lever arm of said foot-end shield passing around both said pulley means and having the other end coupled to the lever arm of said head-end shield; and

means mounted on the foot-end side and head-end side portion of said bucky for respectively engaging one of said first and second pulley means when said bucky is parked at the foot-end or head-end of the table, the engaged pulley means applying a pulling force to the lever arm at the opposite end of the table via said cable for simultaneously moving the respective end shield and center shield to the closed position.

8. The apparatus as defined by claim 6 wherein said operator means comprises:

a first and second pulley assembly respectively located at the head-end and foot-end of the X-ray table to be contacted and actuated by said bucky when said bucky is at a park position at said headend and said foot-end of said table;

a connecting cable having one end connected to said lever arm of said head-end shield and the other end to said lever arm of said foot-end shield and engaging both said pulley assemblies whereby actuation of either one of said pulley assemblies by said bucky causes an actuating force to be exerted by said cable on said lever arm of the shield at the other end of said table which causes the end shield at the other end of the table and said center shield to pivot to said shield position.

9. The apparatus as defined by claim 8 wherein said first and second pulley assembly each comprises a pivoted linkage including:

linkage support means; a first link member pivotally mounted at one end on first pivot means located on said linkage support means, said firstlink member additionally having a pulley wheel'rotatably mounted on the other end; a second pulley wheel rotatably mounted on said first pivot means; and

a second link member pivotally mounted at one end on second pivot means on said linkage support means, said second pivot means being in spaced apart relationship with said first pivot means and at the other end of third pivot means located on said first link member intermediate the ends of said first link member.

10. The apparatus as defined by claim 9 wherein said first link member includes a slot engaging said first pivot means.

11. The apparatus as defined by claim 8 wherein said first and second pulley assembly each comprises a pulley'cluster and wherein said bucky includes means for engaging said connecting cable at said pulley cluster to reduce the slack in said connecting cable and apply a tension force to the opposite end of the table.

12. The apparatus as defined by claim 1 wherein the length dimension of said head-end shield and said footend shield is greater than the corresponding parallel dimension across the front of said bucky and additionally including bucky shield members mounted on either side of the front portion of said bucky having a width substantially equal to the width of said bucky slot. 

1. Bucky slot radiation shield apparatus in an X-ray table for protecting personnel from secondary radiation emanating from a radiation source under said table during an operational mode of said table, comprising in combination: a movable X-ray film cassette holder referred to as a bucky; an X-ray table having a bucky slot comprising a lengthwise opening in the front portion of said table to receive and permit selective movement of said bucky; at least three hinged radiation shields mounted end-to-end adjacent said bucky slot to individually pivot along a same respective edge from a first or open position to permit unobstructed passage of said bucky thereby to a second or shield position for closing the respective slot portion thereat, said three shields comprising a head-end shield, a center shield, and a foot-end shield; bias means to bias said center shield normally to said open position; first means forming part of each of said head-end and foot-end shields to extend over the rear portion of said center shield whereby both the head-end and foot-end shields will be moved to said normally open position along with said center shield and whereby pivoting to said shield position of either the head-end shield or foot-end shield will move said center shield to said shield position also; second means forming part of each of said head-end and foot-end shields for individually actuating said shields when operated from said open position to said shield position; and operator means coupled to said second means of said foot-end and head-end shields, becoming operable in response to said bucky traveling to and arriving at a predetermined location such as at the park position at one end of said table to operate said second means at the other end of said table.
 2. The apparatus as defined by claim 1 wherein said three radiation shields comprise geneRally rectangular door elements having a length dimension substantially greater than the width dimension and additionally including hinge means coupling the same respective lengthwise dimension of said door elements to said table adjacent said bucky slot.
 3. The apparatus as defined by claim 1 wherein said bias means comprises spring bias means.
 4. The apparatus as defined by claim 3 wherein said spring bias means comprises a first second tension spring means respectively having one end coupled to the upper portion of said center shield along the lengthwise dimension opposite from said hinge means and having the respective opposite ends connected to said table.
 5. The apparatus as defined by claim 1 wherein said first means comprises a respective overlapping tab element.
 6. The apparatus as defined by claim 1 wherein said second means comprises a lever arm located on the outer end of each of said head-end and foot-end shields.
 7. The apparatus as defined by claim 6 wherein said operator means comprises: a first and second like pulley means located on said table opposite each other behind said foot-end and head-end radiation shields; a common cable having one end attached to the lever arm of said foot-end shield passing around both said pulley means and having the other end coupled to the lever arm of said head-end shield; and means mounted on the foot-end side and head-end side portion of said bucky for respectively engaging one of said first and second pulley means when said bucky is parked at the foot-end or head-end of the table, the engaged pulley means applying a pulling force to the lever arm at the opposite end of the table via said cable for simultaneously moving the respective end shield and center shield to the closed position.
 8. The apparatus as defined by claim 6 wherein said operator means comprises: a first and second pulley assembly respectively located at the head-end and foot-end of the X-ray table to be contacted and actuated by said bucky when said bucky is at a park position at said head-end and said foot-end of said table; a connecting cable having one end connected to said lever arm of said head-end shield and the other end to said lever arm of said foot-end shield and engaging both said pulley assemblies whereby actuation of either one of said pulley assemblies by said bucky causes an actuating force to be exerted by said cable on said lever arm of the shield at the other end of said table which causes the end shield at the other end of the table and said center shield to pivot to said shield position.
 9. The apparatus as defined by claim 8 wherein said first and second pulley assembly each comprises a pivoted linkage including: linkage support means; a first link member pivotally mounted at one end on first pivot means located on said linkage support means, said first link member additionally having a pulley wheel rotatably mounted on the other end; a second pulley wheel rotatably mounted on said first pivot means; and a second link member pivotally mounted at one end on second pivot means on said linkage support means, said second pivot means being in spaced apart relationship with said first pivot means and at the other end of third pivot means located on said first link member intermediate the ends of said first link member.
 10. The apparatus as defined by claim 9 wherein said first link member includes a slot engaging said first pivot means.
 11. The apparatus as defined by claim 8 wherein said first and second pulley assembly each comprises a pulley cluster and wherein said bucky includes means for engaging said connecting cable at said pulley cluster to reduce the slack in said connecting cable and apply a tension force to the opposite end of the table.
 12. The apparatus as defined by claim 1 wherein the length dimension of said head-end shield and said foot-end shield is greater than the corresponding parallel dimension across the front of said bucky and additionally iNcluding bucky shield members mounted on either side of the front portion of said bucky having a width substantially equal to the width of said bucky slot. 